Abstract
The main objective of this work was to evaluate the genetic control
of Pinus pinaster wood quality by estimating the heritability of wood
density components and its age evolution. The material was collected
from 180 trees by the extraction of an increment core, in a progeny
test at 18 years old. The wood density components were measured using
the X-ray densitometry technique. The highest and most stable age
heritability values were obtained by the earlywood components
(minimum density and earlywood density), followed by the average
ring density. The latewood percentage, ring width and heterogeneity
revealed middle values, while the latewood components (maximum density
and latewood density) always presented the lowest and most unstable
heritability values. Thus, it was concluded that, amongst all components,
the earlywood density mostly depends on genetic effects, and could be used
in future selection and tree breeding programs to improve wood quality.
The inclusion of the latewood components in the selection criterion will
not give any significant genetic advantage.